In a recent paper Huntington lays some of the groundwork for more meaningful discussions between economists and technologists on the apparent underinvestment in energy efficiency, In a discussion illustrated by a production function, he points out that the technical efficiency of economic actors should be treated as an empirical question, Huntington＇s groundwork can be further extended by observing that there is a close relationship between production functions and conservation supply curves, an analytical tool routinely used by technologists, Here we show that a conservation supply curve can be obtained from a production function by a simple transformation.